Control of Gene Expression and Cloning

This set of vocabulary flashcards covers the mechanisms of gene regulation in prokaryotes and eukaryotes, the stages of cell differentiation, X chromosome inactivation details, and various cloning and stem cell technologies.

Gene Expression

The overall process by which information flows from genes to proteins (from genotype to phenotype).

Operon

Cluster of genes with related functions along with some DNA control sequences that get transcribed together.

Repressor protein

A protein that binds to operators to prevent RNA polymerase from attaching to the promoter, thereby inhibiting transcription of operon genes.

Transcription factors

Proteins that can activate or block transcription.

Mature mRNAs

Processed transcripts that are the only form of mRNA allowed to leave the nucleus.

microRNAs

Molecules that can block translation of an mRNA.

Zygote

Fertilized egg cell that results from the union of a female gamete (egg, or ovum) with a male gamete (sperm).

Genetic Equivalency

The principle that all of the cells within a complex multicellular organism contain the same DNA, with no loss or gain of DNA during cell differentiation.

Homeotic gene

Gene encoding a product that causes other genes to be expressed, defining the overall plan of a body.

X Chromosome Inactivation

A process initiated in early embryonic development ($200$ cells) where heavy methylation leads to the inactivation of most genes on one of the X chromosomes.

Barr Body

An inactivated X chromosome resulting from non-coding RNA sticking to it during early embryonic development.

Dosage compensation

The mechanism that ensures males and females have the same effective dose of the genes found on the X chromosome.

Cloning

The process of making an exact copy of a gene, a cell, a tissue, or an entire organism.

Reproductive cloning

A cloning method where an embryo is implanted in a surrogate mother to produce a clone of the donor.

Therapeutic cloning

A cloning method where embryonic stem cells are removed from an embryo and grown in culture to form specialized cells for therapeutic use.

Somatic Cell Nuclear Transplant (SCNT)

A nuclear transplantation technique that involves replacing the nucleus of an egg cell or a zygote with a nucleus removed from an adult body cell.

Dolly

The famous cloned sheep born in $1996$ who later had her first lamb, Bonnie, on April 13th, $1998$.

Adult Stem Cells

Cells that are further along the road to differentiation than embryonic stem (ES) cells and can give rise to only a few related types of specialized cells.

Morphogenesis

One of the three processes involved in embryonic development, alongside cell division and cell differentiation.